/**
 * Copyright 2012 Google Inc. All Rights Reserved.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *    http://www.apache.org/licenses/LICENSE-2.0
 *  
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * Capture various useful debug information.
 */

DOMSnitch.Heuristics.LightDbg = function() {
}

DOMSnitch.Heuristics.LightDbg.getInstance = function() {
  if(!this._lightDbg) {
    this._lightDbg = new DOMSnitch.Heuristics.LightDbg();
  }
  
  return this._lightDbg;
}

DOMSnitch.Heuristics.LightDbg.prototype = {
  collectStackTrace: function(filter) {
    if(!window.USE_DEBUG) {
      return "";
    }
    
    var stack = "";
    try {
      this._dummyCallThatDoesNotExist();
    } catch (e) {
      stack += e.stack;
    }
    
    var filterResult = filter ? filter(stack) : false;
    return !filterResult && stack;
  }
}
